Options Within Interactive Trace; Ending Interactive Trace - IBM TSO/E REXX User Manual

Debugging Execs
The type of tracing is the same as that initiated by issuing the EXECUTIL TS
command.

Options Within Interactive Trace

When you are operating in the interactive debug facility, you have several options
during the pauses that occur between each traced instruction. You can:
v Continue tracing by entering a null line
v Type one or more additional instructions to be processed before the next
v Enter an equal sign (=) to re-execute the last instruction traced
v End interactive tracing as described in the next topic.
Continuing Interactive Tracing: To continue tracing through an exec, simply
press the Enter key to enter a null line during the pause between each traced
instruction. The next traced instruction then appears on the screen. Repeatedly
pressing the Enter key, therefore, takes you from pause point to pause point until
the exec ends.
Typing Additional Instructions to be Processed: During the pause between
traced instructions, you can enter one or more instructions that are processed
immediately. The instruction can be any type of REXX instruction including a
command or invocation to another exec or CLIST. You can also enter a TRACE
instruction, which alters the type of tracing. After you enter the instruction, you might
need to press the Enter key again to resume tracing.
TRACE L
The instruction can also change the course of an exec, such as by assigning a
different value to a variable to force the execution of a particular branch in an IF
THEN ELSE instruction. In the following example, RC is set by a previous
command.
IF RC = 0 THEN
ELSE
If during normal execution, the command ends with other than a 0 return code, the
ELSE path will be taken. To force taking the IF THEN path during interactive trace,
you can change the value of RC as follows during a pause.
RC = 0
Re-executing the Last Instruction Traced: You can re-execute the last
instruction traced by entering an equal sign (=) with no blanks. The language
processor then re-executes the previously traced instruction with values possibly
modified by instructions, if any were entered during the pause.

Ending Interactive Trace

You can end interactive tracing in one of the following ways:
v Use the TRACE OFF instruction.
v Let the exec run until it ends.
v Use the TRACE ? instruction.
v Issue the EXECUTIL TE command.
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instruction is traced
/* Makes the language processor pause at labels only */
DO
instruction1
instruction2
END
instructionA